| 摘要 |
1319638 Coated corrugated paperboard INTERNATIONAL PAPER CO 14 Aug 1970 [21 Aug 1969] 39344/70 Headings B2E and B2L [Also in Division B5] A corrugated paperboard comprises two facing sheets 2 and 4 with a corrugated core 6 therebetween, the corrugations of the core extending transversely across the facing sheets, the edges 8, 10 of the facing sheets at at least one side edge of the core curving inwardly toward each other and into the core with the outer surfaces of the sheets in contact with each other. A method and apparatus for forming the edge sealed paperboard comprises feeding the board through a knife support 348 along at least one side edge of the bond's path, the knife support having a groove with an upper wall 402 and a lower wall 404 for contacting the facing sheets and a knife 396, and passing the board through dies 418, 438 for rolling the edges of the facing sheets inwardly toward each other and for tucking the end of the rolled edge into the slit cut in the core by the knife. A bead of thermoplastic material may be applied to the tucked edge of the board. |
